Hi Martin,
One of the underlining themes I see in this issue 85 and some others
(text equivalents, table summary, etc) is validation.
Validation errors/warnings can create a teachable moment. A moment of
great opportunity. A time to educate. A time to get action. A time to
get people to actually fix their pages.
In rejecting Steve's bug [1] Ian said:
<quote>
It seems to me that we _should_ be calling authors out on this kind of mistake.
Just because people do something doesn't mean we should make it valid - after
all, we made <font> invalid, along with many other things. Conformance is about
trying to advise authors to do the right thing.
I have added text to the spec that encourages conformance checkers to be very
careful about how they complain about these issues, by the way, so that authors
aren't encouraged to remove ARIA support but are instead encouraged to use the
right elements.
<unquote>
I agree with the principle that we should be calling authors out on mistakes.
Just because authors do (or don't do in the case of text alternatives)
something doesn't mean we should make it valid.
But what is a mistake?
WAI-CG figured this out for Issue 31-text alternatives and issued
their consensus document [3] on the matter. I filed Bug 8716 [2] to
ensure the spec is made absolutely clear what text alternative options
are valid and sanctioned. Flagging errors in this case is very good
thing indeed.I know this personally because I uses the W3C HTML/XHTML
validator as a web accessibility teaching tool. I have my students use
it in the accessibility classes that I teach to flag missing text
alternatives. One of their first lessons is to validate HTML on the
W3C site to ensure that it is error-free and that they have indeed
examined each image. It makes a BIG impression that text alternatives
are mandatory not just for WCAG but as well for valid HTML4 and XHTML.
It is an undeniable advertisement that it is needed. It is a *first
step* in getting that vital message across.
But I digress...getting back to Issue 85 [4]. I think it would be good
for this task force figure out what a mistake is. In Henri Sivonen's
bug comment [5] he said:
<quote>
The ARIA support of Validator.nu, which hasn't been updated to spec
yet, allows and has always allowed <a role=button>.
It's unfortunate that the accessibility part is the only part where it's
realistic to programmatically detect semantic abuse. However, I think it's more
likely that authors would break accessibility than that authors would stop the
semantic abuse in this case if whined at by a validator. (That is, I disagree
with the editor's resolution of this bug.)
<unquote>
I ask task force members:
1. Is accessibility helped or hurt by a validator calling an error in
the case of Issue 85?
2. Why do you think so?
Best Regards,
Laura
[1] http://www.w3.org/Bugs/Public/show_bug.cgi?id=8000#c1
[2] http://www.w3.org/Bugs/Public/show_bug.cgi?id=8716
[3] http://www.w3.org/2009/06/Text-Alternatives-in-HTML5
[4] http://www.w3.org/html/wg/tracker/issues/85
[5] http://www.w3.org/Bugs/Public/show_bug.cgi?id=8000#c3
--
Laura L. Carlson